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author | Oliver Upton <oliver.upton@linux.dev> | 2022-11-07 21:59:34 +0000 |
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committer | Marc Zyngier <maz@kernel.org> | 2022-11-10 14:43:47 +0000 |
commit | 946fbfdf336b811479e024136c7cabc00157b6b9 (patch) | |
tree | 17f10d2a0e9a901c9cfe096b9a5fe80b1a32367e /arch/arm64 | |
parent | 0ab12f3574db6cb432917a667f9392a88e8f0dfc (diff) | |
download | linux-stable-946fbfdf336b811479e024136c7cabc00157b6b9.tar.gz linux-stable-946fbfdf336b811479e024136c7cabc00157b6b9.tar.bz2 linux-stable-946fbfdf336b811479e024136c7cabc00157b6b9.zip |
KVM: arm64: Make leaf->leaf PTE changes parallel-aware
Convert stage2_map_walker_try_leaf() to use the new break-before-make
helpers, thereby making the handler parallel-aware. As before, avoid the
break-before-make if recreating the existing mapping. Additionally,
retry execution if another vCPU thread is modifying the same PTE.
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Reviewed-by: Ben Gardon <bgardon@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221107215934.1895478-1-oliver.upton@linux.dev
Diffstat (limited to 'arch/arm64')
-rw-r--r-- | arch/arm64/kvm/hyp/pgtable.c | 26 |
1 files changed, 12 insertions, 14 deletions
diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index b9f0d792b8d9..238f29389617 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -804,18 +804,17 @@ static int stage2_map_walker_try_leaf(const struct kvm_pgtable_visit_ctx *ctx, else new = kvm_init_invalid_leaf_owner(data->owner_id); - if (stage2_pte_is_counted(ctx->old)) { - /* - * Skip updating the PTE if we are trying to recreate the exact - * same mapping or only change the access permissions. Instead, - * the vCPU will exit one more time from guest if still needed - * and then go through the path of relaxing permissions. - */ - if (!stage2_pte_needs_update(ctx->old, new)) - return -EAGAIN; + /* + * Skip updating the PTE if we are trying to recreate the exact + * same mapping or only change the access permissions. Instead, + * the vCPU will exit one more time from guest if still needed + * and then go through the path of relaxing permissions. + */ + if (!stage2_pte_needs_update(ctx->old, new)) + return -EAGAIN; - stage2_put_pte(ctx, data->mmu, mm_ops); - } + if (!stage2_try_break_pte(ctx, data->mmu)) + return -EAGAIN; /* Perform CMOs before installation of the guest stage-2 PTE */ if (mm_ops->dcache_clean_inval_poc && stage2_pte_cacheable(pgt, new)) @@ -825,9 +824,8 @@ static int stage2_map_walker_try_leaf(const struct kvm_pgtable_visit_ctx *ctx, if (mm_ops->icache_inval_pou && stage2_pte_executable(new)) mm_ops->icache_inval_pou(kvm_pte_follow(new, mm_ops), granule); - smp_store_release(ctx->ptep, new); - if (stage2_pte_is_counted(new)) - mm_ops->get_page(ctx->ptep); + stage2_make_pte(ctx, new); + if (kvm_phys_is_valid(phys)) data->phys += granule; return 0; |